58. federal law prohibits 21 year olds from purchasing pistols.

Connecticut law prohibits possession of "assault weapons" and does not issue handgun permits to anyone less than 21 years if age.

Then there's this from the Connecticut state code:
Sec. 29-34. False statement or information in connection with sale or transfer of pistol or revolver prohibited. Sale or transfer to person under twenty-one years of age prohibited. Temporary transfers. Penalties. (a) No person shall make any false statement or give any false information connected with any purchase, sale, delivery or other transfer of any pistol or revolver. Any person violating any provision of this subsection shall be guilty of a class D felony.

(b) No person shall sell, barter, hire, lend, give, deliver or otherwise transfer to any person under the age of twenty-one years any pistol or revolver, except that a pistol or revolver may be temporarily transferred to any person only for the use by such person in target shooting or on a firing or shooting range, provided such use is otherwise permitted by law and is under the immediate supervision of a person eligible to possess a pistol or revolver. Any person violating any provision of this subsection shall be guilty of a class D felony for which one year of the sentence imposed may not be suspended or reduced by the court.

(c) Any pistol or revolver found in the possession of any person in violation of any provision of this section shall be forfeited.